Reinforced Polythene Building Membranes
Fire retardent
Polythene vapour check and roof underlay

835 Vapour Check is a reinforced polythene vapour check for use inside insulation in wall and roof construction to prevent warm, moist air from inside the building condensing within the insulation. The reinforced construction resists tears and punctures that can quickly compromise the performance of ordinary building films. The material is not readily ignitable, and will melt but not continue burning in small fires.

Construction

835 Vapour Check is a multilayer membrane with FR additive polythene for low ignitability and a woven polypropylene reinforcing mesh to resist tearing and punctures. Grade 835 is opaque white in colour and both surfaces have a smooth appearance.

Technical Data

Basis Weight (g/m2)		243 g
Tensile Strength	-MD	6.3 kN/m
	-CD	6.1 kN/m
Nail Tear Resistance	-MD	170
	-CD	160 N
MVTR		0.48 g/m2/d
Vapour Resistance		428 MNs/g

Fixing/Sitework

The membrane is laid over the liner panel and all seams sealed with a suitable butyl double-sided adhesive tape. It is covered by the insulation, then a breather sheet, and the external roof covering fixed.

Availability

Standard Roll Size	2000mm x 50m
Roll Weight	23.5 kg

All information given in good faith and is believed to be accurate. Technical data is based on laboratory testing and represents average values. Specific lots may vary above or below these values.